fix issue regarding not pre-filtering instance types by provider cons…

…traints (#1543)

pkg/cloudprovider/fake/cloudprovider.go

@@ -109,6 +109,8 @@ func (c *CloudProvider) GetInstanceTypes(_ context.Context, _ *v1alpha5.Provider
 		NewInstanceType(InstanceTypeOptions{
 			Name:         "arm-instance-type",
 			Architecture: "arm64",
+			CPU:          resource.MustParse("16"),
+			Memory:       resource.MustParse("128Gi"),
 		}),
 	}, nil
 }

pkg/controllers/provisioning/scheduling/node.go

@@ -19,6 +19,8 @@ import (
 
 	v1 "k8s.io/api/core/v1"
 
+	"github.com/aws/karpenter/pkg/utils/sets"
+
 	"github.com/aws/karpenter/pkg/apis/provisioning/v1alpha5"
 	"github.com/aws/karpenter/pkg/cloudprovider"
 	"github.com/aws/karpenter/pkg/utils/resources"
@@ -41,6 +43,16 @@ func NewNode(constraints *v1alpha5.Constraints, instanceTypeOptions []cloudprovi
 		if !instanceTypes.Has(it.Name()) {
 			continue
 		}
+
+		// provisioner constraints can't exclude the instance type by arch or OS
+		if !constraints.Requirements.Get(v1.LabelArchStable).Has(it.Architecture()) {
+			continue
+		}
+		if constraints.Requirements.Get(v1.LabelOSStable).Intersection(
+			sets.NewSet(it.OperatingSystems().List()...)).Len() == 0 {
+			continue
+		}
+
 		included := false
 		// and the instance type must have some valid offering combination per the provisioner constraints
 		for _, off := range it.Offerings() {
@@ -61,6 +73,7 @@ func NewNode(constraints *v1alpha5.Constraints, instanceTypeOptions []cloudprovi
 	}
 	return n
 }
+
 func (n Node) Compatible(pod *v1.Pod) error {
 	podRequirements := v1alpha5.NewPodRequirements(pod)
 	if err := n.Constraints.Requirements.Compatible(podRequirements); err != nil {

pkg/controllers/provisioning/scheduling/suite_test.go

@@ -1585,6 +1585,20 @@ var _ = Describe("Instance Type Compatibility", func() {
 		}
 		Expect(nodeNames.Len()).To(Equal(2))
 	})
+	It("should exclude instance types that are not supported by the provider constraints (arch)", func() {
+		provisioner.Spec.Requirements.Requirements = []v1.NodeSelectorRequirement{
+			{
+				Key:      v1.LabelArchStable,
+				Operator: v1.NodeSelectorOpIn,
+				Values:   []string{v1alpha5.ArchitectureAmd64},
+			},
+		}
+		pod := ExpectProvisioned(ctx, env.Client, selectionController, provisioners, provisioner,
+			test.UnschedulablePod(test.PodOptions{ResourceRequirements: v1.ResourceRequirements{
+				Limits: map[v1.ResourceName]resource.Quantity{v1.ResourceCPU: resource.MustParse("14")}}}))
+		// only the ARM instance has enough CPU, but it's not allowed per the provisioner
+		ExpectNotScheduled(ctx, env.Client, pod[0])
+	})
 	It("should launch pods with different operating systems on different instances", func() {
 		provisioner.Spec.Requirements.Requirements = []v1.NodeSelectorRequirement{
 			{